Skinny Chickens

So my flock of chickens (with the exception of my bantams) are soooo skinny. I don't understand why. I am feeding waterfowl food (recently switched to turkey feed due to higher protein levels) and scratch. I also offer crushed granite. They are locked in a barn with an outside "run". They have access to food ALWAYS. Every time I pick one up, it disgusts me how skinny they are. Does anyone know what is going on??? I have dewormed with Valbazen but that doesn't seem to help. Any suggestions would be appreciated. Occasionally I have a death too and it's always a super skinny one.

So worms and mites are the answers I am getting. I will deworm again I guess, not sure how the reg sized chickens would be the only ones affected. They are housed with bantams and ducks. Everybody else doing well.....worms not visual in poop and haven't seen mites - have looked them over but will try again at night. I was hoping someone would say it's the wrong food and I could easily fix that.....

Reason being, if you only wormed once the wormer cannot kill the eggs that are present at the worming. You have to worm again 10-14 days later, dosing each chx indivually (orally). Each dosage should be 1/2 cc for standard birds, 1/4 cc for bantams or young birds. Does anyone do a 3 rd round? I do in my goats but not my chx.

You won't see worms in stool unless they have a very heavy worm load. Even then you won't see it in every poo so the chances u see them are slim. A sure fire way to know if they have worms is bring fresh stool to a bet where they will run a fecal. The worm eggs are what they're looking for under a microscope. This is what I would do.

Thank you Bagawk, however I am a vet tech. I have run fecals but find nothing. It has been a while since I sent one to the lab so maybe I will try that next. I understand the science behind deworming so I know it has to be repeated. I will try another round of Valbazen (twice) and see what happens. Even so, it seems weird that the bantams wouldn't be affected.

Have you observed the flock's feeding behavior? Sometimes when you have only a single feeder one or two individuals in the flock will chase away the others so they can't get their fill. One solution for that problem is to set up multiple feeding stations.

You might also try switching feeds to see if that helps, and perhaps look at how much scratch and other treats you're offering the flock.